A touch panel, as the latest information input equipment at present, can realize human-machine interaction easily, conveniently and naturally and provides a new multimedia human-machine interaction mode for people. Due to the advantages of sensitive touch response, supporting multi-point touch and the like, the touch panel greatly meets people's visual and tactile enjoyment.
Generally, a touch panel at least includes a display panel for displaying and a touch panel for touching. At present, touch panels may be classified into add on mode touch panels, on cell touch panels and in cell touch panels according to the structures thereof. In other words, sensing electrodes Rx and driving electrodes Tx are formed inside or outside or on a surface of the display panel. Although touch panels are of various different structures, each panel includes sensing electrodes Rx and driving electrodes Tx connected to corresponding sensing signal lines and driving signal lines, respectively. When a human body touches a touch panel, the touch panel “senses” the touch of the human body by detecting a change in an electric field between a sensing electrode Rx and a driving electrode Tx so as to realize a touch function.
As one of the best liquid crystal display devices in the current liquid crystal display field, Advanced Super Dimension Switch (ADSDS, ADS for short) mode liquid crystal display devices have gradually become popular with consumers due to their wide angle of view, higher contrast ratio, higher resolution and brighter color. In an ADS mode liquid crystal display device having a touch function, capacitor-mutual inductance type “sensing” touch is generally employed, and therefore, a sensing electrode Rx and a driving electrode Tx are generally arranged in such an interlaced manner that the sensing electrode Rx and the driving electrode Tx are at least partially overlapped in an orthographic projection direction. To ensure a normal rate of change in touch capacitance and realize “sensing”, in such structure, it is required that facing area between the sensing electrode Rx and the driving electrode Tx cannot be too large, so as to ensure that node capacitance therebetween can meet touch requirements. However, the arrangement manner of the sensing electrodes Rx and the driving electrodes Tx commonly adopted at present is likely to cause too large coupling capacitance therebetween and thus affect the touch sensitivity. Moreover, the sensing electrodes Rx are generally arranged along longitudinal strips of a black matrix (for the current color filter substrate, the width of longitudinal strips is less than that of transverse strips). As the narrow longitudinal strips in the black matrix cannot completely cover the pattern of the sensing electrodes Rx, the sensing electrodes Rx will impede image display in the normal display condition, so that the display effect is influenced.
Therefore, how to improve touch sensitivity and improve image display effect has become a technical problem to be urgently solved at present.